Functions as a sorting receptor in the Golgi compartment required for the intracellular sorting and delivery of soluble vacuolar proteins, like carboxypeptidase Y (CPY) and proteinase A. May execute multiple rounds of sorting by cycling between the late Golgi and a prevacuolar endosome-like compartment. Binds the Golgi-modified P2 form of CPY, and this interaction is dependent on the presence of an intact CPY vacuolar protein sorting signal.